Snaky coworker

so

I’m so pissed. I work at a restaurant and there’s a co-worker I’ve been working with for over 5 years. We’ve been cool, never had too many problems. Until lately, she decided to become a snake and taking MY tables that were either assigned to me or given to me by the hosts or another server who didn’t want them. She has twice now gotten angry if I get said table (meanwhile she has a full section and the table I get isn’t even in her section). She even yelled at me about it in front of the manager. Did the managers do anything though? Of course not. Then tonight, same thing happened except she just waltzed over to the table and greeted them before I could. It was awkward when I came by and they had already been talked to. I told the manager but he let her keep it. This manager and I are friends and have been since I started and he told me she’s really pissing him and everyone off and is planning to talk to the GM and other managers about this chick. im planning to talk to corporate too. i did the wrong thing by venting to my friendly co-workers, but they also said shes doing the same shit to them. I like this job, it pays well and most people are cool but this shit makes me feel so uncomfortable I dont even know what to do. and i feel like such an idiot for not confronting her and just avoiding even talking to her, especially i didnt say anything to her tonight. we also havent talked in a month and i just saw she blocked me on Facebook (I went to block her lol). Idk what to do 😞